Bug 847045 - Avoid frequent ExcludeType bailouts. r=nbp
Bug 841579 - Tests to make sure that removing elements from a document midway through load don't inhibit onload. rs=khuey

--HG--
extra : rebase_source : 4ac911cdb4039a8e1a0531b7171e4f5cf3641bef
Bug 841579 - If we start a decode (or a decode is already started) at the time OnStopRequest is fired, wait around for it to finish decoding before firing onload/onerror. r=khuey

--HG--
extra : rebase_source : b2ca068840c2e4effc8c93fd9e5effe122e8b45e